You want a tesla coil "deterrent":
No-one will go near it
I have a Mongoose in my VW van, and it's OK. The alarm is a bit quiet, but it seems to work well. It's set up to immobilse all sorts of things ont he van - ECU power, fuel pump etc.
There are some alarms that will allow a car to be started, but cut the fuel 20 or 30 seconds after the car is started, if not propoerly disarmed - they're great, because a stolen car, stopped halfway through an intersection with the alarm blaring attracts a lot of attention